1. Field of the Invention
The present invention relates to devices for fabricating liquid crystal display devices, and more particularly, to a substrate conveyance device for fabricating a liquid crystal display device, where a substrate conveyance device conveys a substrate of a liquid crystal panel.
2. Discussion of the Related Art
Liquid crystal display (LCD) devices have good picture quality, are thin and light weight, and consume comparatively little power. As such, many mobile display device applications use LCD devices. Besides the mobile display devices, such as monitors for notebook computers, LCD devices are also used in other applications, including television monitors which receive and display a broadcast signal, and desktop computer monitors.
In general, a LCD device has a liquid crystal panel for displaying a picture and a driving unit for applying a driving signal to the liquid crystal panel. Additionally, the LCD device has a pair of substrates bonded together where a liquid crystal layer is injected in a gap between the substrates.
Individual substrates, or bonded substrates having individual substrates bonded together, are conveyed to and from various positions during fabrication with a conveyance device, such as a robot arm.
The robot arm, or the conveyance device, has a plurality of hands for conveying the individual substrates or the bonded substrates, to various positions during fabrication. When the robot arm conveys the substrates to and from various positions, the robot arm has either the individual substrates or the bonded substrates on a surface of each hand of the robot arm.
Furthermore, the related art robot arm has a plurality of projections from the surface of the hand that minimize a contact area between the robot arm and the substrate.
However, projections of the related art robot arm concentrate a load on portions of the individual substrates or the bonded substrates where each of the projections contact the substrates, thereby bending the portions.
Particularly, if the bent portion has a spacer formed thereon for maintaining an appropriate gap between one pair of substrates, the appropriate gap may not be maintained, which may cause a defective orientation of the liquid crystals.
Moreover, the related art conveyance device does not align substrates. Thus, a separate alignment device is required to align bonded substrates when a substrate moves to different positions during a fabrication process. For example, a separate alignment device is required when a substrate is moved to a cutting apparatus that cuts the bonded substrates into unit panels. Consequently, time and costs associated with fabricating LCD devices increase.